// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "cc/layers/layer_list_iterator.h"

#include <memory>

#include "base/containers/adapters.h"
#include "cc/animation/animation_host.h"
#include "cc/test/fake_compositor_frame_sink.h"
#include "cc/test/fake_impl_task_runner_provider.h"
#include "cc/test/fake_layer_tree_host.h"
#include "cc/test/fake_layer_tree_host_impl.h"
#include "cc/test/test_task_graph_runner.h"
#include "cc/trees/layer_tree_impl.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace cc {
namespace {

    // Layer version unit tests

    TEST(LayerListIteratorTest, VerifyTraversalOrder)
    {
        // Unfortunate preamble.
        FakeLayerTreeHostClient client;
        TestTaskGraphRunner task_graph_runner;
        auto animation_host = AnimationHost::CreateForTesting(ThreadInstance::MAIN);
        std::unique_ptr<FakeLayerTreeHost> host_ptr = FakeLayerTreeHost::Create(
            &client, &task_graph_runner, animation_host.get());
        FakeLayerTreeHost* host = host_ptr.get();

        // This test constructs the following tree.
        // 1
        // +-2
        // | +-3
        // | +-4
        // + 5
        //   +-6
        //   +-7
        // We expect to visit all seven layers in that order.
        scoped_refptr<Layer> layer1 = Layer::Create();
        scoped_refptr<Layer> layer2 = Layer::Create();
        scoped_refptr<Layer> layer3 = Layer::Create();
        scoped_refptr<Layer> layer4 = Layer::Create();
        scoped_refptr<Layer> layer5 = Layer::Create();
        scoped_refptr<Layer> layer6 = Layer::Create();
        scoped_refptr<Layer> layer7 = Layer::Create();

        std::unordered_map<int, int> layer_id_to_order;
        layer_id_to_order[layer1->id()] = 1;
        layer_id_to_order[layer2->id()] = 2;
        layer_id_to_order[layer3->id()] = 3;
        layer_id_to_order[layer4->id()] = 4;
        layer_id_to_order[layer5->id()] = 5;
        layer_id_to_order[layer6->id()] = 6;
        layer_id_to_order[layer7->id()] = 7;

        layer2->AddChild(std::move(layer3));
        layer2->AddChild(std::move(layer4));

        layer5->AddChild(std::move(layer6));
        layer5->AddChild(std::move(layer7));

        layer1->AddChild(std::move(layer2));
        layer1->AddChild(std::move(layer5));

        host->SetRootLayer(std::move(layer1));

        int i = 1;
        for (auto* layer : *host->GetLayerTree()) {
            EXPECT_EQ(i++, layer_id_to_order[layer->id()]);
        }
        EXPECT_EQ(8, i);
    }

    TEST(LayerListIteratorTest, VerifySingleLayer)
    {
        // Unfortunate preamble.
        FakeLayerTreeHostClient client;
        TestTaskGraphRunner task_graph_runner;
        auto animation_host = AnimationHost::CreateForTesting(ThreadInstance::MAIN);
        std::unique_ptr<FakeLayerTreeHost> host_ptr = FakeLayerTreeHost::Create(
            &client, &task_graph_runner, animation_host.get());
        FakeLayerTreeHost* host = host_ptr.get();

        // This test constructs a tree consisting of a single layer.
        scoped_refptr<Layer> layer1 = Layer::Create();
        std::unordered_map<int, int> layer_id_to_order;
        layer_id_to_order[layer1->id()] = 1;
        host->SetRootLayer(std::move(layer1));

        int i = 1;
        for (auto* layer : *host->GetLayerTree()) {
            EXPECT_EQ(i++, layer_id_to_order[layer->id()]);
        }
        EXPECT_EQ(2, i);
    }

    TEST(LayerListIteratorTest, VerifyNullFirstLayer)
    {
        // Ensures that if an iterator is constructed with a nullptr, that it can be
        // iterated without issue and that it remains equal to any other
        // null-initialized iterator.
        LayerListIterator<Layer> it(nullptr);
        LayerListIterator<Layer> end(nullptr);

        EXPECT_EQ(it, end);
        ++it;
        EXPECT_EQ(it, end);
    }

    TEST(LayerListReverseIteratorTest, VerifyTraversalOrder)
    {
        // Unfortunate preamble.
        FakeLayerTreeHostClient client;
        TestTaskGraphRunner task_graph_runner;
        auto animation_host = AnimationHost::CreateForTesting(ThreadInstance::MAIN);
        std::unique_ptr<FakeLayerTreeHost> host_ptr = FakeLayerTreeHost::Create(
            &client, &task_graph_runner, animation_host.get());
        FakeLayerTreeHost* host = host_ptr.get();

        // This test constructs the following tree.
        // 1
        // +-2
        // | +-3
        // | +-4
        // + 5
        //   +-6
        //   +-7
        // We expect to visit all seven layers in reverse order.
        scoped_refptr<Layer> layer1 = Layer::Create();
        scoped_refptr<Layer> layer2 = Layer::Create();
        scoped_refptr<Layer> layer3 = Layer::Create();
        scoped_refptr<Layer> layer4 = Layer::Create();
        scoped_refptr<Layer> layer5 = Layer::Create();
        scoped_refptr<Layer> layer6 = Layer::Create();
        scoped_refptr<Layer> layer7 = Layer::Create();

        std::unordered_map<int, int> layer_id_to_order;
        layer_id_to_order[layer1->id()] = 1;
        layer_id_to_order[layer2->id()] = 2;
        layer_id_to_order[layer3->id()] = 3;
        layer_id_to_order[layer4->id()] = 4;
        layer_id_to_order[layer5->id()] = 5;
        layer_id_to_order[layer6->id()] = 6;
        layer_id_to_order[layer7->id()] = 7;

        layer2->AddChild(std::move(layer3));
        layer2->AddChild(std::move(layer4));

        layer5->AddChild(std::move(layer6));
        layer5->AddChild(std::move(layer7));

        layer1->AddChild(std::move(layer2));
        layer1->AddChild(std::move(layer5));

        host->SetRootLayer(std::move(layer1));

        int i = 7;

        for (auto* layer : base::Reversed(*host->GetLayerTree())) {
            EXPECT_EQ(i--, layer_id_to_order[layer->id()]);
        }

        EXPECT_EQ(0, i);
    }

    TEST(LayerListReverseIteratorTest, VerifySingleLayer)
    {
        // Unfortunate preamble.
        FakeLayerTreeHostClient client;
        TestTaskGraphRunner task_graph_runner;
        auto animation_host = AnimationHost::CreateForTesting(ThreadInstance::MAIN);
        std::unique_ptr<FakeLayerTreeHost> host_ptr = FakeLayerTreeHost::Create(
            &client, &task_graph_runner, animation_host.get());
        FakeLayerTreeHost* host = host_ptr.get();

        // This test constructs a tree consisting of a single layer.
        scoped_refptr<Layer> layer1 = Layer::Create();
        std::unordered_map<int, int> layer_id_to_order;
        layer_id_to_order[layer1->id()] = 1;
        host->SetRootLayer(std::move(layer1));

        int i = 1;
        for (auto* layer : base::Reversed(*host->GetLayerTree())) {
            EXPECT_EQ(i--, layer_id_to_order[layer->id()]);
        }
        EXPECT_EQ(0, i);
    }

    TEST(LayerListReverseIteratorTest, VerifyNullFirstLayer)
    {
        // Ensures that if an iterator is constructed with a nullptr, that it can be
        // iterated without issue and that it remains equal to any other
        // null-initialized iterator.
        LayerListReverseIterator<Layer> it(nullptr);
        LayerListReverseIterator<Layer> end(nullptr);

        EXPECT_EQ(it, end);
        ++it;
        EXPECT_EQ(it, end);
    }

    // LayerImpl version unit tests

    TEST(LayerListIteratorTest, VerifyTraversalOrderImpl)
    {
        // Unfortunate preamble.
        FakeImplTaskRunnerProvider task_runner_provider;
        TestTaskGraphRunner task_graph_runner;
        std::unique_ptr<CompositorFrameSink> compositor_frame_sink = FakeCompositorFrameSink::Create3d();
        FakeLayerTreeHostImpl host_impl(&task_runner_provider, &task_graph_runner);
        host_impl.SetVisible(true);
        EXPECT_TRUE(host_impl.InitializeRenderer(compositor_frame_sink.get()));

        // This test constructs the following tree.
        // 1
        // +-2
        // | +-3
        // | +-4
        // + 5
        //   +-6
        //   +-7
        // We expect to visit all seven layers in that order.
        std::unique_ptr<LayerImpl> layer1 = LayerImpl::Create(host_impl.active_tree(), 1);
        std::unique_ptr<LayerImpl> layer2 = LayerImpl::Create(host_impl.active_tree(), 2);
        std::unique_ptr<LayerImpl> layer3 = LayerImpl::Create(host_impl.active_tree(), 3);
        std::unique_ptr<LayerImpl> layer4 = LayerImpl::Create(host_impl.active_tree(), 4);
        std::unique_ptr<LayerImpl> layer5 = LayerImpl::Create(host_impl.active_tree(), 5);
        std::unique_ptr<LayerImpl> layer6 = LayerImpl::Create(host_impl.active_tree(), 6);
        std::unique_ptr<LayerImpl> layer7 = LayerImpl::Create(host_impl.active_tree(), 7);

        layer2->test_properties()->AddChild(std::move(layer3));
        layer2->test_properties()->AddChild(std::move(layer4));

        layer5->test_properties()->AddChild(std::move(layer6));
        layer5->test_properties()->AddChild(std::move(layer7));

        layer1->test_properties()->AddChild(std::move(layer2));
        layer1->test_properties()->AddChild(std::move(layer5));

        host_impl.active_tree()->SetRootLayerForTesting(std::move(layer1));
        host_impl.active_tree()->BuildLayerListForTesting();

        int i = 1;
        for (auto* layer : *host_impl.active_tree()) {
            EXPECT_EQ(i++, layer->id());
        }
        EXPECT_EQ(8, i);
    }

    TEST(LayerListIteratorTest, VerifySingleLayerImpl)
    {
        // Unfortunate preamble.
        FakeImplTaskRunnerProvider task_runner_provider;
        TestTaskGraphRunner task_graph_runner;
        std::unique_ptr<CompositorFrameSink> compositor_frame_sink = FakeCompositorFrameSink::Create3d();
        FakeLayerTreeHostImpl host_impl(&task_runner_provider, &task_graph_runner);
        host_impl.SetVisible(true);
        EXPECT_TRUE(host_impl.InitializeRenderer(compositor_frame_sink.get()));

        // This test constructs a tree consisting of a single layer.
        std::unique_ptr<LayerImpl> layer1 = LayerImpl::Create(host_impl.active_tree(), 1);
        host_impl.active_tree()->SetRootLayerForTesting(std::move(layer1));
        host_impl.active_tree()->BuildLayerListForTesting();

        int i = 1;
        for (auto* layer : *host_impl.active_tree()) {
            EXPECT_EQ(i++, layer->id());
        }
        EXPECT_EQ(2, i);
    }

    TEST(LayerListIteratorTest, VerifyNullFirstLayerImpl)
    {
        // Ensures that if an iterator is constructed with a nullptr, that it can be
        // iterated without issue and that it remains equal to any other
        // null-initialized iterator.
        LayerListIterator<LayerImpl> it(nullptr);
        LayerListIterator<LayerImpl> end(nullptr);

        EXPECT_EQ(it, end);
        ++it;
        EXPECT_EQ(it, end);
    }

    TEST(LayerListReverseIteratorTest, VerifyTraversalOrderImpl)
    {
        // Unfortunate preamble.
        FakeImplTaskRunnerProvider task_runner_provider;
        TestTaskGraphRunner task_graph_runner;
        std::unique_ptr<CompositorFrameSink> compositor_frame_sink = FakeCompositorFrameSink::Create3d();
        FakeLayerTreeHostImpl host_impl(&task_runner_provider, &task_graph_runner);
        host_impl.SetVisible(true);
        EXPECT_TRUE(host_impl.InitializeRenderer(compositor_frame_sink.get()));

        // This test constructs the following tree.
        // 1
        // +-2
        // | +-3
        // | +-4
        // + 5
        //   +-6
        //   +-7
        // We expect to visit all seven layers in reverse order.
        std::unique_ptr<LayerImpl> layer1 = LayerImpl::Create(host_impl.active_tree(), 1);
        std::unique_ptr<LayerImpl> layer2 = LayerImpl::Create(host_impl.active_tree(), 2);
        std::unique_ptr<LayerImpl> layer3 = LayerImpl::Create(host_impl.active_tree(), 3);
        std::unique_ptr<LayerImpl> layer4 = LayerImpl::Create(host_impl.active_tree(), 4);
        std::unique_ptr<LayerImpl> layer5 = LayerImpl::Create(host_impl.active_tree(), 5);
        std::unique_ptr<LayerImpl> layer6 = LayerImpl::Create(host_impl.active_tree(), 6);
        std::unique_ptr<LayerImpl> layer7 = LayerImpl::Create(host_impl.active_tree(), 7);

        layer2->test_properties()->AddChild(std::move(layer3));
        layer2->test_properties()->AddChild(std::move(layer4));

        layer5->test_properties()->AddChild(std::move(layer6));
        layer5->test_properties()->AddChild(std::move(layer7));

        layer1->test_properties()->AddChild(std::move(layer2));
        layer1->test_properties()->AddChild(std::move(layer5));

        host_impl.active_tree()->SetRootLayerForTesting(std::move(layer1));
        host_impl.active_tree()->BuildLayerListForTesting();

        int i = 7;

        for (auto* layer : base::Reversed(*host_impl.active_tree())) {
            EXPECT_EQ(i--, layer->id());
        }

        EXPECT_EQ(0, i);
    }

    TEST(LayerListReverseIteratorTest, VerifySingleLayerImpl)
    {
        // Unfortunate preamble.
        FakeImplTaskRunnerProvider task_runner_provider;
        TestTaskGraphRunner task_graph_runner;
        std::unique_ptr<CompositorFrameSink> compositor_frame_sink = FakeCompositorFrameSink::Create3d();
        FakeLayerTreeHostImpl host_impl(&task_runner_provider, &task_graph_runner);
        host_impl.SetVisible(true);
        EXPECT_TRUE(host_impl.InitializeRenderer(compositor_frame_sink.get()));

        // This test constructs a tree consisting of a single layer.
        std::unique_ptr<LayerImpl> layer1 = LayerImpl::Create(host_impl.active_tree(), 1);
        host_impl.active_tree()->SetRootLayerForTesting(std::move(layer1));
        host_impl.active_tree()->BuildLayerListForTesting();

        int i = 1;
        for (auto* layer : base::Reversed(*host_impl.active_tree())) {
            EXPECT_EQ(i--, layer->id());
        }
        EXPECT_EQ(0, i);
    }

    TEST(LayerListReverseIteratorTest, VerifyNullFirstLayerImpl)
    {
        // Ensures that if an iterator is constructed with a nullptr, that it can be
        // iterated without issue and that it remains equal to any other
        // null-initialized iterator.
        LayerListReverseIterator<LayerImpl> it(nullptr);
        LayerListReverseIterator<LayerImpl> end(nullptr);

        EXPECT_EQ(it, end);
        ++it;
        EXPECT_EQ(it, end);
    }

} // namespace
} // namespace cc
